There are several fields that are using deprecated fields, which should be fixed e.g.
commons.js:1696 Error: You are accessing BasePackage#data which is now deprecated in favor of referencing schema fields directly on the BasePackage instance.
Deprecated since Version 10
Backwards-compatible support will be removed in Version 12
at logCompatibilityWarning (commons.js:1685)
at System.get data [as data] (commons.js:11720)
at heart.js:1
at new Promise (<anonymous>)
at Object.fn (heart.js:1)
at Function.#call (foundry.js:724)
at Function.callAll (foundry.js:681)
at Game.setupGame (foundry.js:7854)
at async Game._initializeGameView (foundry.js:8899)
at async Game.initialize (foundry.js:7727)
There are several fields that are using deprecated fields, which should be fixed e.g.